no. 9
Group theory/Algebraic geometry
Automorphisms of T‾
[Automorphismes de T‾]

Présenté par : Claire Voisin

Biswas, Indranil1 ; Senthamarai Kannan, Subramaniam2 ; Nagaraj, Donihakalu Shankar3
1 School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
2 Chennai Mathematical Institute, H1, SIPCOT IT Park, Siruseri, Kelambakkam 603103, India
3 The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
Comptes Rendus. Mathématique, Tome 353 (2015) no. 9, pp. 785-787.

Soit G‾ la compactification magnifique d'un groupe algébrique affine G défini sur C, dont le centre est trivial et tel que G≠PSL(2,C). Soit T⊂G un tore maximal, et soit T‾ son adhérence dans G‾. Nous montrons que T est égal à la composante connexe contenant l'élément neutre du groupe d'automorphismes de la variété T‾.

Let G‾ be the wonderful compactification of a simple affine algebraic group G defined over C such that its center is trivial and G≠PSL(2,C). Take a maximal torus T⊂G, and denote by T‾ its closure in G‾. We prove that T coincides with the connected component, containing the identity element, of the group of automorphisms of the variety T‾.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2015.06.006
Biswas, Indranil 1 ; Senthamarai Kannan, Subramaniam 2 ; Nagaraj, Donihakalu Shankar 3

1 School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
2 Chennai Mathematical Institute, H1, SIPCOT IT Park, Siruseri, Kelambakkam 603103, India
3 The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India 
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Biswas, Indranil; Senthamarai Kannan, Subramaniam; Nagaraj, Donihakalu Shankar. Automorphisms of $ \stackrel{‾}{T}$. Comptes Rendus. Mathématique, Tome 353 (2015) no. 9, pp. 785-787. doi : 10.1016/j.crma.2015.06.006. http://www.numdam.org/articles/10.1016/j.crma.2015.06.006/

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